Distal detachment mechanisms for vascular devices

Abstract

A system for delivering an expandable implant into the vasculature of a patient, including an elongated core element having a proximal end accessible exterior to the patient and a distal end including at least one feature for engaging a proximal portion of the implant in a collapsed state. The system further includes an expansion limiter having an inner diameter and a length sufficient to cover the proximal portion of the implant and to retain the proximal portion in the collapsed state, and at least one elongated member having a distal end connected to the expansion limiter and a proximal end accessible exterior to the patient to enable proximal movement of the expansion limiter to release the implant.

What is claimed is: 
     
       1. A system for delivering an expandable implant into the vasculature of a patient, comprising:
 an elongated core element having a proximal end accessible exterior to the patient and a distal end including at least one feature for engaging a proximal portion of the implant in a collapsed state; 
 an expansion limiter having an inner diameter and a length sufficient to cover the proximal portion of the implant and to retain the proximal portion in the collapsed state; and 
 at least one elongated member having a distal end connected to the expansion limiter and a proximal end accessible exterior to the patient to enable proximal movement of the expansion limiter to immediately release and expand the implant. 
 
     
     
       2. The system of  claim 1  further including a delivery catheter having an inner diameter sufficiently large to accommodate the core element, the implant in the collapsed state, and the expansion limiter. 
     
     
       3. The system of  claim 1  wherein the feature is a projection from the core element. 
     
     
       4. The system of  claim 1  wherein the feature is retractable relative to the core element to assist release of the implant. 
     
     
       5. The system of  claim 1  wherein the expansion limiter is substantially cylindrical. 
     
     
       6. The system of  claim 1  wherein the expansion limiter has overlapping side edges. 
     
     
       7. The system of  claim 1  wherein the core element is formed of metal. 
     
     
       8. The system of  claim 1  wherein the core element includes a solid wire in proximity to the feature. 
     
     
       9. The system of  claim 1  wherein the member is a filament. 
     
     
       10. The system of  claim 9  wherein the filament is a wire. 
     
     
       11. The system of  claim 1  wherein the core element and the member are formed from a hypotube. 
     
     
       12. The system of  claim 11  wherein the feature is retractable into the hypotube to assist release of the implant.